01: /*
02: * <copyright>
03: *
04: * Copyright 2002-2004 BBNT Solutions, LLC
05: * under sponsorship of the Defense Advanced Research Projects
06: * Agency (DARPA).
07: *
08: * You can redistribute this software and/or modify it under the
09: * terms of the Cougaar Open Source License as published on the
10: * Cougaar Open Source Website (www.cougaar.org).
11: *
12: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
13: * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
14: * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
15: * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
16: * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
17: * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
18: * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
22: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23: *
24: * </copyright>
25: */
26:
27: package org.cougaar.core.wp.resolver;
28:
29: import org.cougaar.core.component.Service;
30: import org.cougaar.core.component.ServiceAvailableEvent;
31: import org.cougaar.core.component.ServiceAvailableListener;
32: import org.cougaar.core.component.ServiceBroker;
33: import org.cougaar.core.component.ServiceListener;
34: import org.cougaar.core.component.ServiceRevokedListener;
35:
36: /**
37: * A utility class to hide late-binding {@link Service} lookups.
38: * <p>
39: * This could be moved into org.cougaar.core.component.
40: */
41: public class ServiceFinder {
42:
43: private ServiceFinder() {
44: }
45:
46: public interface Callback {
47: void foundService(Service s);
48: }
49:
50: public static boolean findServiceLater(final ServiceBroker sb,
51: final Class cl, final Object requestor, final Callback cb) {
52: final Object req = (requestor == null ? ServiceFinder.class
53: : requestor);
54: if (sb.hasService(cl)) {
55: Service s = (Service) sb.getService(req, cl, null);
56: cb.foundService(s);
57: return true;
58: }
59: ServiceAvailableListener sal = new ServiceAvailableListener() {
60: public void serviceAvailable(ServiceAvailableEvent ae) {
61: if (cl.isAssignableFrom(ae.getService())) {
62: Service s = (Service) sb.getService(req, cl, null);
63: cb.foundService(s);
64: //sb.removeServiceListener(this);
65: }
66: }
67: };
68: sb.addServiceListener(sal);
69: return false;
70: }
71: }
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